1. Field of the Invention
The present invention relates to bag packs of thermoplastic film type bags wherein conventionally used headers are avoided. The bag pack is designed to eliminate the waste which is a part of headered bags and to provide an easy support and removal of the bags from a bag holder.
2. Background of the Invention
Plastic bags are used for numerous items, many in the food and hardware field and the like. It is very common to buy these plastic bags in headered bag packs which are then supported on a dispenser. The header is attached to the dispenser by holes or other means and a line of weakening is provided for tearing the bag off the header and thereby removing it for use. Such a construction is shown in Daniels U.S. Pat. No. 5,590,784. This construction, of course, leaves the plastic bag header when the bag pack is depleted. The header is then simply discarded. Since the plastic film to make the bag costs money, the plastic in the header costs money and discarding it increases the cost of the use of the bag.
It is therefore an object of this invention to provide a bag pack without a header. Headerless bag packs are also shown in my U.S. Pat. No. 5,575,393 but the top bags of this invention operate on a different principle. The bags of this invention have a supporting aperture or hole which is designed to tear directly upwardly toward the mouth or the top of the bag. The bags themselves in this bag pack are sealed together by a small seal of either hot seal or cold weld type preferably on opposite sides of the supporting aperture or hole so that when the user wishes to remove a bag from the bag pack supported on a bag pack holder he simply grasps the bottom of the top bag and pulls down and away from the bag holder and the bag is removed ready for use. When the bags are all used up there is nothing left to discard since there is no header on the bag pack.
In accordance with the present invention, there is provided a thermoplastic film bag pack which comprises a plurality of bags stacked in at least general registration in a lay flat condition.
Each of the bags includes a top wall and a bottom wall, gusetted side walls are sometimes provided, although they are not necessary, and heat sealed across the bottom of the front and rear walls and the side walls. Bags of this nature may be made from tubular stock which is cut at the desired areas to provide the size of bag needed and the bags are then heat sealed together to provide the bag pack. Alternatively, sheet or film material may be used to make the bags. As previously mentioned, most plastic bags are headered and include an upper header portion from which the bags are removed along a line of weakening. The bag pack of this invention has no header and therefore eliminates the problem of discarding unused plastic material.
The bag pack of this invention has an aperture adjacent the top or opening of the bag which is preferably in a tear drop like shape so that when pressure is applied to the bag as part of a bag pack suspended on a dispenser, the bag will tear in the direction of the top opening of the bag. The bag pack itself is held together by small weak seals, generally two seals, which are on opposite sides of the aperture and adjacent the bottom thereof although the seals may be placed in any convenient location along or near the top of the bag so long as they maintain the bag in a bag pack condition. Either heat seals or cold weld seals are useable.
The cold seal is formed by protruding a dull pointed pin/needle of approximately xe2x85x9xe2x80x3 diameter through the pack and into a rubber pad or some other similar material. This action acts to extrude one bag through to the other and thus temporarily welding the bags together. The rubber has to be of sufficient durometer (70 minimum) as not to deform downwardly when the pin/needle is protruded into the pad.
The hot seal uses a very small diameter pin approximately {fraction (1/16)}xe2x80x3 diameter that is heated to an appropriate temperature, for the material used, to melt and seal. This action is in conjunction with the action of extruding the material of the bag as the pin protrudes through into a Teflon pad. This Teflon paid is necessary as the rubber would burn or melt at the temperatures required to seal most bag materials. This seal, if tiny as stated above, will also only create a temporary seal that takes little force to separate once on a dispenser.
These temporary seals will allow the bag pack to be loaded onto the dispenser in a predetermined number without the unnecessary fumbling with loose bags. Once on the dispenser minimal force is necessary to separate the bags at the point of the seal while leaving the others still welded together. The seals in combination with the teardrop shaped mounting hole leaves no scrap once all the bags are removed.
In one method of preparing the bag packs of this invention, tubular stock is cut into the desired length to provide the size of bag required and the bags are then heat sealed together in a simple operation to provide the preferred double heat seals. The teardrop shaped hole is then punched through the bag pack. In use, the bag pack is simply suspended from a bag dispenser, which is normally a rod, and they are used by simply grasping the bottom of the bag on top of the pack and pulling it from the dispenser by breaking the seals and tearing through the teardrop shaped hole in the direction of the mouth or opening of the bag.
It is therefore an object of the present invention to provide a pack of thermoplastic film bags which are headerless and which are sealed together, either heat or cold seals, adjacent the top of the bag and have a teardrop shaped supporting hole which is designed to allow the bag to tear off from a support rod in the direction of the mouth of the bag thereby providing a useable bag with minimum waste.
Other objects and advantages of the present invention will become apparent to those skilled in the art upon the reading of the specification and the claims appended hereto.